Chapter 3 Flashcards
The type of energy in X-rays, radio waves, microwaves, & visible light
Electro magnetic energy
properties of electromagnetic energy
Frequency, wavelength, velocity and amplitude
An uninterrupted ordered sequence
Energy continuum
The smallest quantity of any type of electromagnetic energy, it maybe pictured as quantum
Photon
A small bundle of energy
Quantum
Who is James clerk Maxwell
In late 19th century, he showed that visible light has both electric and magnetic properties
Speed of light?
Velocity
What is the constant s1 unit of velocity and its constant British unit
Constant SI unit is 3x10^8 m/s
Constant British unit 186,000 mi/s
What is the velocity of electromagnetic radiation?
3 x 10^8 m/s
The interactions among different energies forces or masses
Field
It governs the interaction of different masses
Gravitational fields
It governs the interactions of electrostatic charges
Electric field
It governs the interaction of magnetic poles
Magnetic field
The variation in the movement of photons in electrical and magnetic fields, identical except for their amplitude
Sine wave
The width of a waveform, it is not related to wavelength or frequency
Amplitude
It describes variations in electric and magnetic fields as photons travels with velocity
Sine wave model of electromagnetic energy
- It is equal to the number of crests or valley that pass the point of an observer per unit time
- it is inversely proportional to the wavelength
- the rate of rise and fall
Frequency
Si unit of frequency?
(Hz)
The number of wavelengths that pass a point of observation per second
Frequency
Distance from one crest to another
Wavelength
Three wave parameters
Velocity, frequency and wavelength
A continuum of electromagnetic energy
Electro magnetic spectrum
Three regions important to radiologic science
Visible light region, X-ray region, radio frequency region
Viewing condition of a radiographic and fluoroscopic images are critical diagnosis
Visible light region
Fundamental producing high quality radiograph
Xray region
With the introduction of MRI, become more important in medical imaging
Radio frequency region
- The wave of moving molecules
- it require matter
- cannot exist in vacuum
Ultrasound
Not a part of the electromagnetic spectrum
Diagnostic ultra sound
It occupies the smallest segment of electromagnetic spectrum, it is described in terms of wave length
Visible light
The deviation of course that occurs when photos of visible light traveling in straight lines pass from transparent medium to another
Refraction
2 invisible light
Infrared and UV light
Infrared
Longer than visible light, shorter than microwaves it heats any substance on which it shines (radiant heat)
UV light
It causes sunburn , lies between visible light and ionizing radiation
- Very short wavelength RF
- higher than broadcast RF
- lower than infrared
Microwave
Higher energy and lower wave length
Ionizing radiation
*It is emitted from the electron cloud
* it is produced in diagnostic imaging systems
Xrays
*It comes from inside the nucleus of radioactive atom
* it is emitted spontaneously from radioactive material
Gamma rays
They behave more like waves
Visible light photons
They behave more like particles
Xray photons
The principle that states that both wave and particle concepts must be retained ‘ because wave like properties are exhibited in some experiments and particle-like properties are exhibited in others.
Wave particle duality
- they are measured in meters
- they interact with antennas
Radio and TV waves
- It is measured in centimeter
- it interacts with hotdogs and hamburgers
Microwave
- it is measured in nanometer
- it interacts with rods and comes of the eye
Visible light
It interacts with molecules
UV light
It interacts with electrons
Xrays
The reduction in intensity that results from scattering and absorption
Electromagnetic energy attenuation
Structures that absorb X-rays
Radiopaque (example: bones)
Structures that transmit X-rays
Radiolucent (example: lung tissue)
It states that the intensity of radiation at a location is inversely proportional to the square of distance from the source of radiation
Inverse square law
Who is Max Planck?
He synthesized our understanding of electromagnetic radiation, On 1918: he received the Nobel prize
It states that energy may be transformed from one form to another but cannot be created on destroyed
Law of conservation of energy
States that matter can be neither created nor destroyed
Law of conservation of matter
All radiation with wavelength longer than xray
Wave phenomenon
